4/3-way high response directional control valve pilot operated with electrical feedback and integrated electronics (OBE)

Transcription

1 4/3-way high response directional control valve pilot operated with electrical feedback and integrated electronics (OE) ype 4WRDE Nominal size to 35 Component series 5X Maximum operating pressure 3 bar Maximum flow 3 L/min Overview of contents Contents Information on available spare parts: age Features Ordering details 2 referred types 3 Symbols 3 Function, section, valve features 4 echnical data 5 and 6 Connection allocation / lock circuit diagram for the integrated electronics (OE) 6 Electrical connection, plug-in connector 7 and 8 Characteristic curves 9 to 4 Unit dimensions to 2 Features RE 2993/9.7 Replaces: 8.4 H//D 68 /2 ilot operated 3-stage high response directional control valve with electrical feedback of the main spool and integrated electronics (OE) cquisition of the main spool position by means of an inductive position transducer 2-stage pilot control valve, type 4WS2EM 6-2X/... articularly suitable for closed loop position, velocity, pressure and force control with simultaneous high requirements in dynamic response and response sensitivity Subplate mounting: orting pattern to ISO 44 (NS to 35) Signal integration of the valve s closed loop control circuit, the supply to the position measuring system and the control of the pilot control valve are carried out via the integrated control electronics

2 2/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Ordering details Electrically operated 3-stage high response directional control valve of 4-way design with integrated electronics Nominal size = Nominal size 6 = 6 Nominal size 25 = 25 Nominal size 27 = 27 Nominal size 32 = 32 Nominal size 35 = 35 Spool symbols 4WRDE 5X 6L 24 K9 R * a b a b With spool symbol E-, W-, V-: : : q Vmax q V /2 : : q V /2 q Vmax = E = E- = W = W- = V = V- = Q2- Note: With W, W- spools, there is, in the neutral position, a connection from to and to with approx. 3 % of the relevant nominal cross-section. L = = 6L = No code = E = E = = M = 2) V = Further details in clear text ) Only available with spool variants E-; W and V and with the L (linear) characteristic curve form 2) Suitable for mineral oil (HL, HL) according to DIN 524 R = R rings NR seals FKM seals No code = Without sandwich plate directional valve WG2 = With sandwich plate directional valve 24 V =, lug-in connector Z4 lug-in connector separate order see page 8 Electrical connections K9 = Without plug-in connector with component plug lug-in connector separate order see pages 7 and 8 ilot oil flow External pilot oil supply, external pilot oil return Internal pilot oil supply, external pilot oil return Internal pilot oil supply, internal pilot oil return External pilot oil supply, internal pilot oil return Supply voltage 24 = +24 V DC Nominal size 6 servo pilot control 5X = Component series to 59 ( to 59: unchanged installation and connection dimensions) Characteristic curve form Linear Linear with fine control range Nominal flow 25 ) = or = or = For nominal size 25 = or 2 = For nominal size 6 22 = or 3 = For nominal size 25 = For nominal size 27 4 = or 6 = For nominal size 32 = For nominal size 35 see pages to 4

3 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G 3/2 referred types ype NS 4WRDE VL-5X/6L24EK9/MR 4WRDE VL-5X/6L24K9/MR 4WRDE VL-5X/6L24EK9/MR 4WRDE VL-5X/6L24K9/MR 4WRDE VL-5X/6L24K9/WG2MR 4WRDE V-L-5X/6L24K9/WG2MR ype NS6 4WRDE 6 V25L-5X/6L24K9/MR 4WRDE 6 V25L-5X/6L24K9/WG2MR 4WRDE 6 V2L-5X/6L24EK9/MR 4WRDE 6 V2L-5X/6L24K9/MR 4WRDE 6 V2L-5X/6L24K9/WG2MR Symbols (simplified, detailed) ype 4WRDE 5X E. Internal pilot oil flow X a a b a b ype 4WRDE. 5X External pilot oil supply, internal pilot oil return a a b G Y Material No. R R R R R99633 R Detailed Example: ype 4WRDE -5X/ External pilot oil supply, external pilot oil return ilot control valve 2 Main valve 3 Sandwich plate directional valve 4 Integrated electronics (OE) G G X Material No. R R R99533 R R b b 2 4 ype NS25 4WRDE 25 V22L-5X/6L24K9/MR 4WRDE 25 V3L-5X/6L24K9/MR 4WRDE 25 V3L-5X/6L24K9/WG2MR 4WRDE 25 V-3L-5X/6L24EK9/WG2MR ype NS32 4WRDE 32 V6L-5X/6L24K9/MR 4WRDE 32 V6L-5X/6L24K9/WG2MR 4WRDE 32 V-6L-5X/6L24K9/WG2MR ype 4WRDE 5X External pilot oil flow X a a a b a b ype 4WRDE. 5X E Internal pilot oil supply, external pilot oil return a a b Example: ype 4WRDE -5X/ WG2 Sandwich plate directional valve for centralising the main stage External pilot oil supply, external pilot oil return Y Y G G G X b Y Material No. R99592 R R R97262 Material No. R R R b b 3 2 4

4 4/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Function, section, valve features Valves of the 4WRDE type are 3-stage high response directional control valves. hey control or regulate the rate and direction of a flow and are primarily used in closed loop circuits for various tasks. hese valves basically consist of the following assemblies: 2-stage pilot control valve comprising a torque motor () and a hydraulic amplifier (5) designed as a flapper jet valve and spool sleeve unit (6) as a flow amplifier stage for the control of the third stage (7). hird stage (7) for flow control. n inductive position transducer (8), the core (9) of which is attached to main spool () of the third stage. he position of the spool () is acquired via the inductive position transducer (8). he signal integration of the valve closed loop control circuit, the supply to the position measuring system and the control of the pilot control valve are carried out via the control electronics which are integrated in the valve. he differential voltage generated by the command/actual value comparison is amplified within the control electronics and passed on to the first stage of the valve as a control deviation. his signal moves the flapper plate (2) between the two control jets (3., 3.2). hus, a pressure differential is generated between the two control chambers (.,.2). he control spool (4) is displaced and passes a corresponding oil flow into the control chamber (2. or 2.2). he spool () and the attached core (9) of the inductive position transducer (8) are displaced until the actual value signal once more tallies with the command value signal. In the controlled condition, the spool () is held in the position defined by the command value X Y 7 9 he spool stroke is proportional to the command value. o control the flow, there is a relevant control opening to which the flow is proportional. his the result of the position of the control spool () with regard to the control lands (3). he valve dynamics are optimised via the electrical amplification. he control electronics are integrated in the valve (oscillator, demodulator). Valve features he third stage basically consists of components from our proportional valves. he control lands of spool and housing for V spools are ground to match each other. he zero point adjustment at the main stage zero point is factory pre-set and can via a potentiometer in the control electronics be adjusted within a range of ± 8 % of the nominal stroke. he integrated control electronics can be accessed by removing a plug in the housing. If the pilot control valve or the control electronics are exchanged, then these have to be recalibrated. ny calibration must only be carried out by trained personnel. Maintenance work on the pilot control valve must only be carried out by osch Rexroth personnel. However, the replacement of the replacement part, consisting of a filter element and a seal, is excluded from this - Material no. R Care must be taken to ensure that the seal is correctly located and that the plugs are correctly tightened. he tightening torque of the cover screws is 2 Nm. Changing the zero point can lead to damage to the system and must only be carried out by trained personnel! lug g7 Main stage zero point ±8 % max. adjustable Danger! he sensitivity of the main stage must not be adjusted!

5 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G 5/2 echnical data (for applications outside these parameters, please consult us!) General Nominal sizes NS Weight kg 6,8 8,9,2,5 35,2 7 Installation and commissioning guidelines referably horizontal, see RE 77 Storage temperature range C 2 to +8 mbient temperature range C 2 to +6 Hydraulic (measured with HL 46, ϑ Oil = 4 C ±5 C) Max. operating pressure Max. Return pressure orts,, External pilot oil bar to 3 to 3 to 3 to 2 to 3 to 3 ort X supply ) bar 2 (min. 25) 2 (min. 25) 2 (min. 25) orts,, Internal pilot oil supply bar 2 (min. 25) 2 (min. 25) 2 (min. 25) ort Internal pilot oil bar ressure peaks < permissible return External pilot oil bar to 3 to 2 to 2 to 2 to 2 to 2 return ort Y Internal pilot oil return bar ressure peaks < permissible Nominal flow q Vnom ± % at Δp = bar 2) Δp = valve pressure differential in bar L/min 25 Flow in the main valve (max. permissible) L/min ilot oil flow at ports X or Y with a stepped form of input signal from to % (3 bar) L/min 2,7 5,4 6,5 6,5 8,2 24,2 ressure fluid Mineral oil (HL, HL) according to DIN 524, other pressure fluids upon request ressure fluid temperature range C 2 to +8; preferably +4 to + Viscosity range mm 2 /s 2 to 38 Max. permissible degree of pressure fluid contamination Cleanliness class ilot control valve Class 7//2 3) according to ISO 446 (c) Main valve Class 2/8/ 3) Hysteresis %,2 Response sensitivity %, Zero point calibration (factory pre-set) 4) % Zero point drift with change in: ressure fluid temperature % / 2 K,7 Operating pressure % / bar,5 Return flow pressure to % from p %,2 ) For optimum system characteristics we recommend, with pressures over 2 bar, an external pilot oil supply. 2) q Vnom = Nominal flow (of the entire valve) in L/min with a V spool ) he cleanliness classes stated for the components must be adhered too in hydraulic systems. Effective filtration prevents faults from occurring and at the same time increases the component service life. For the selection of filters, see catalogue sheets RE 7, RE 76, RE 8, RE 86 and RE 88. 4) Referring to the pressure signal characteristic curve (V spool)

6 6/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 echnical data (for applications outside these parameters, please consult us!) Electrical Voltage type Signal type Valve protection according to EN 6529 Control electronics R7 mplitude Command value ± V D E U U Controller Current controller Ref. potential at E and pos. com. value at D results in U I flow from in the main stage of the WRDE R8 R5 valve Command value attenuation Zero point main stage +24 V V F C R2 ~ = DC nalogue I65 with mounted and fixed plug-in connector Integrated in the valve Note! For details regarding the environmental simulation test covering EMC (electro-magnetic compatibility), climate and mechanical loading, see RE 2993-U (declaration regarding environmental compatibility). Electrical connections lock circuit diagram for the integrated electronics (OE) ctual position value (± V) Enable 4 24 V Note: Zero point main stage Dither Matching amplifier R2 Oscillator = ~ Demodulator = ~ Sensitivity main stage C D Red rown lack Servo valve Inductive position transducer (differential transformer) Electrical signals (e.g. actual value or enable) led out via valve control electronics must not be used to switch off the machine's safety-relevant functions! (See also the European Standard "Safety requirements of fluid technology systems and components hydraulics", EN 982!)

7 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G 7/2 Electrical connection, plug-in connector (dimensions in mm) lug-in connector for control valve lug-in connector according to DIN EN Separate order under Material No. R92267 (plastic version) 9 lug-in connector according to DIN EN Separate order under Material No. R (metal version) Ø28,4 Ø27 lug-in connector compatible to VG , size 4-6S Separate order under Material No. R939 (metal version) Ø28,5 ) With hydraulic pressure present and a non activated enable, the spool of the main stage is displaced into the end position and the cylinder axis moves out of its position with its maximum velocity. y using a WG2 sandwich plate directional valve between the pilot valve and main stage, one can unload the control chambers from the pilot control valve to the main spool, and the spool of the main stage is Component plug allocation Contact Signal 24 VDC (2 to 28 VDC); full bridge rectification with 22 µf Supply voltage smoothed; I max = 27 m V ) Enable (the valve circuit is activated) C 4 to 24 VDC Differential amplifier input (command value) D E ± V 2; 3) ctual value F ± V (to contact ) Ø6,5 Ø Ø8 Ø3,5 Ø6,5 Ø9,5 SW2 centered in the middle position or held in a preferred position by springs. s a result, the cylinder axis moves out of its position at its minimum velocity. 2) positive command value at D with respect to E results in a flow from to in the main stage! 3) Current input ± m optional, input resistance kω; state 28 in the ordering details. C C D F D E C F E D E F

8 8/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Electrical connection, plug-in connector (dimensions in mm) lug-in connector for sandwich plate directional valves e.g. WG2 according to DIN EN and ISO 44 Separate order under Material No. R97 (plastic version) 53 27, ,5 3 Ø22,5

9 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G 9/2 Characteristic curves (measured at ν = 32 mm 2 /s and ϑ = 4 C) ressure-signal-characteristic curves (V spool) Flow-command value functions (at bar valve pressure differential or 5 bar per control land) Spool with characteristic curve L Spool with characteristic curve Flow in % Flow in % Command value in % Spool symbol Q , Command value in % U E in % U EN ) Zero flow of the main stage (V spool) without pilot control valve 8, Δp 2,5 2,5,5,5,5 2 2,5 L in % U p E S in % Spool symbol V Spool symbol E or W Measured at p S = bar Flow in % of the nominal flow Flow in % 2,5, Spool symbol Q2- L Command value in % U EN Spool symbol V Spool symbol E or W ) For spool symbol Q2- and Q2- L Measured at p S = bar

10 /2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Characteristic curves (measured with HL 46 at 4 C ±5 C) ransient function with a stepped form of electrical input signal Stroke in % Signal change in % ime in ms Frequency response characteristic curves +5 mplitude relationship in d Frequency in Hz Flow-load function at max. valve opening (tolerance ± %) Flow in L/min Measured at: ilot control valve ort X = 4 bar Main valve ort = bar Valve pressure differential in bar hase angle in Measured at: ilot control valve ort X = 4 bar Main valve ort = bar NS Signal ± % Signal ±25 % Signal ±5 % = Recommended flow limitation (flow velocity 3 m/s)

11 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G /2 Characteristic curves (measured with HL 46 at 4 C ± 5 C) ransient function with a stepped form of electrical input signal Stroke in % ime in ms Frequency response characteristic curves mplitude relationship in d Frequency in Hz Flow-load function at max. valve opening (tolerance ± %) Flow in L/min Signal change in % Valve pressure differential in bar 9 hase angle in Measured at: ilot control valve ort X = 4 bar Main valve ort = bar Measured at: ilot control valve ort X = 4 bar Main valve ort = bar Signal ± % Signal ±25 % Signal ±5 % = Recommended flow limitation (flow velocity 3 m/s) NS6

12 2/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Characteristic curves (measured with HL 46 at 4 C ±5 C) NS25 and 27 ransient function with a stepped form of electrical input signal Stroke in % ime in ms Frequency response characteristic curves +5 mplitude relationship in d Frequency in Hz Flow-load function at max. valve opening (tolerance ± %) Flow in L/min 87 3 NG27 3 NG25 Signal change in % 22 NG Valve pressure differential in bar 9 hase angle in Measured at: ilot control valve ort X = 4 bar Main valve ort = bar Measured at: ilot control valve ort X = 4 bar Main valve ort = bar Signal ± % Signal ±25 % Signal ±5 % = Recommended flow limitation (flow velocity 3 m/s)

13 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G 3/2 Characteristic curves (measured with HL 46 at 4 C ±5 C) ransient function with a stepped form of electrical input signal Stroke in % Signal change in % ime in ms Frequency response characteristic curves +5 mplitude relationship in d Frequency in Hz Flow-load function at max. valve opening (tolerance ± %) 6 Flow in L/min Valve pressure differential in bar hase angle in Measured at: ilot control valve ort X = 4 bar Main valve ort = bar Measured at: ilot control valve ort X = 4 bar Main valve ort = bar NS32 Signal ± % Signal ±25 % Signal ±5 % = Recommended flow limitation (flow velocity 3 m/s)

14 4/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Characteristic curves (measured with HL 46 at 4 C ±5 C) ransient function with a stepped form of electrical input signal Signal change in % Stroke in % ime in ms Frequency response characteristic curves +5 mplitude relationship in d Frequency in Hz Flow-load function at max. valve opening (tolerance ± %) Flow in L/min 2 Valve pressure differential in bar hase angle in 4 Measured at: ilot control valve ort X = 4 bar Main valve ort = bar Measured at: ilot control valve ort X = 4 bar Main valve ort = bar NS35 Signal ± % Signal ±25 % Signal ±5 % = Recommended flow limitation (flow velocity 3 m/s)

15 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G /2 Unit dimensions NS (dimensions in mm) , ,5 (76,5) 27 X ilot control valve 25,5 F 245, F4 8 F2 2 Sandwich plate directional valve (only included in version " WG2") 3 Cabling 4 Main valve 5 Name plate 6 Identical seal rings for ports,,, and 7 Identical seal rings for ports X and Y 8 Machined valve mounting surface, position of the ports according to ISO (ports X, Y as required) 9 Space required to remove the plug-in connector lug-in connector, separate order, see page 7 F3 Y 9 6,/ 2 7 Rzmax 4 Required surface finish of the valve mounting face 8 86 (26) Suplates according to catalogue sheet RE 454 (separate order) G 534/ (G3/4) G 535/ (G3/4) with ports X and Y G 536/ (G) with ports X and Y Valve fixing screws (separate order) he following valve fixing screws are recommended: 4 S.H.C.S. ISO4762-M6x45-.9-flZn-24h-L (friction value according to VD 235-) ightening torque M = 3.5 Nm ± % Material no. R93258 he tightening torques given are guiding values, if the screws with the given friction coefficients are used and if they are tightened by means of a torque wrench. Note: he tightening torque relates to the maximum operating pressure!

16 6/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Unit dimensions NS6 (dimensions in mm) 94 2 (64) F 2 ilot control valve F5 G F2 X Y F4 G2 F6 F Sandwich plate directional valve (only included in version " WG2") 3 Cabling 4 Main valve 5 Name plate 6 Identical seal rings for ports,, and 7 Identical seal rings for ports X and Y 8 Machined valve mounting surface, position of the ports according to ISO (ports X, Y as required) 9 Space required to remove the plug-in connector lug-in connector, separate order, see page 7 Locating pin (2 pieces) 9, Ø3 9,/ Rzmax 4 Required surface finish of the valve mounting surface Suplates according to catalogue sheet RE 456 (separate order) G 72/ (G3/4) G 72/2 (M27 x 2) G 74/ (G) G 74/2 (M33 x 2) Valve fixing screws (separate order) he following valve fixing screws are recommended: 2 S.H.C.S. ISO4762-M6x6-.9-flZn-24h-L (friction value according to VD 235-) ightening torque M = 2,2 Nm ±2 % Material no. R93 4 S.H.C.S. ISO4762-Mx6-.9-flZn-24h-L (friction value according to VD 235-) ightening torque M = 58 Nm ±2 % Material no. R (226) he tightening torques given are guiding values, if the screws with the given friction coefficients are used and if they are tightened by means of a torque wrench. Note: he tightening torque relates to the maximum operating pressure!

17 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G 7/2 Unit dimensions NS25 (dimensions in mm) 2 (42) F F4 X G2 F Y 8 33 ilot control valve 2 Sandwich plate directional valve (only included in version " WG2") 3 Cabling 4 Main valve 5 Name plate 6 Identical seal rings for ports,, and 7 Identical seal rings for ports X and Y 8 Machined valve mounting surface, position of the ports to ISO (ports X, Y as required) 9 Space required to remove the plug-in connector lug-in connector, separate order, see page 7 Locating pin (2 pieces) F6 G F2 F ,8 Ø6 6,/ 7 Rzmax 4 Required surface finish of the valve mounting surface Suplates according to catalogue sheet RE 458 (separate order) G / (G) G 4/ (G /4) G 4/8 (flange) G 6/ (G /2) 8 26 (256) Valve fixing screws (separate order) he following valve fixing screws are recommended: 6 S.H.C.S. ISO4762-M2x6-.9-flZn-24h-L (friction value according to VD 235-) ightening torque M = Nm ±2 % Material no. R932 he tightening torques given are guiding values, if the screws with the given friction coefficients are used and if they are tightened by means of a torque wrench. Note: he tightening torque relates to the maximum operating pressure! Note: Only install the sandwich plate directional valve between the main valve and the adaptor plate!

18 8/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Unit dimensions NS27 (dimensions in mm) 24 (44) F F4 ilot control valve X 98 G2 F F6 G F2 Y F Sandwich plate directional valve (only included in version " WG2") 3 Cabling 4 Main valve 5 Name plate 6 Identical seal rings for ports,, and 7 Identical seal rings for ports X and Y 8 Machined valve mounting surface, position of the ports to ISO (ports X, Y as required) 9 Space required to remove the plug-in connector Ø6 6,/ Rzmax 4 2 Required surface finish of the valve mounting face lug-in connector, separate order, see page 7 Locating pin (2 pieces) 8 4 (27) Suplates according to catalogue sheet RE 458 (separate order) G / (G) G 4/ (G /4) G 4/8 (flange) G 6/ (G /2) Valve fixing screws (separate order) he following valve fixing screws are recommended: 6 S.H.C.S. ISO4762-M2x6-.9-flZn-24h-L (friction value according to VD 235-) ightening torque M = Nm ±2 % Material no. R932 he tightening torques given are guiding values, if the screws with the given friction coefficients are used and if they are tightened by means of a torque wrench. Note: he tightening torque relates to the maximum operating pressure! Note: Only install the sandwich plate directional valve between the main valve and the adaptor plate!

19 RE 2993/9.7 4WRDE Hydraulics osch Rexroth G 9/2 Unit dimensions NS32 (dimensions in mm) 2 (54,5) 2,5 2, F F4 ilot control valve X G2 F5 257 F ,5 2 Sandwich plate directional valve (only included in version " WG2") 3 Cabling 4 Main valve 5 Name plate 6 Identical seal rings for ports,, and 7 Identical seal rings for ports X and Y 8 Machined valve mounting surface, position of the ports according to ISO /9/44--5 (ports X, Y as required) 9 Space required to remove the plug-in connector lug-in connector, separate order, see page 7 Locating pin (2 pieces) G 8 Y F2 F3 9 9, 49 3 Ø6 6,/ Rzmax 4 97 Required surface finish of the valv mounting surface 8 2 (282) Suplates according to catalogue sheet RE 46 (separate order) G 7/ (G /2) G 7/2 (M48 x 2) G 8/ (flange) Valve fixing screws (separate order) he following valve fixing screws are recommended: 6 S.H.C.S. ISO4762-M2x8-.9-flZn-24h-L (friction value according to VD 235-) ightening torque M = 34 Nm ±2 % Material no. R he tightening torques given are guiding values, if the screws with the given friction coefficients are used and if they are tightened by means of a torque wrench. Note: he tightening torque relates to the maximum operating pressure!

20 2/2 osch Rexroth G Hydraulics 4WRDE RE 2993/9.7 Unit dimensions NS32 (dimensions in mm) ,7 36 (8,7) 465,8 2, , F F4 X G2 ilot control valve 2 Sandwich plate directional valve (only included in version " WG2") 3 Cabling 4 Main valve 5 Name plate 6 Identical seal rings for ports,, and osch Rexroth G Hydraulics Zum Eisengießer 9786 Lohr am Main, Germany hone +49 () / 8- Fax +49 () / documentation@boschrexroth.de F5 F6 G Y F2 F Identical seal rings for ports X and Y 8 Machined vale mounting surface, position of the ports according to ISO (ports X, Y as required) in deviation from the standard: orts,, and Ø mm ca ,,/ Rzmax 4 9 Space required to remove the plug-in connector lug-in connector, separate order, see page 7 Locating pin (2 pieces) Suplates according to catalogue sheet RE 46 (separate order) G 7/ (G /2) G 7/2 (M48 x 2) G 8/ (flange) Valve fixing screws (separate order) he following valve fixing screws are recommended: 6 S.H.C.S. ISO4762- M2x-.9-flZn-24h-L 6 97 Ø Required surface finish of the valve mounting surface (friction value according to VD 235-) ightening torque M = 34 Nm ±2 % Material no. R93386 he tightening torques given are guiding values, if the screws with the given friction coefficients are used and if they are tightened by means of a torque wrench. Note: he tightening torque relates to the maximum operating pressure! his document, as well as the data, specifications and other informations set forth in it, are the exclusive property of osch Rexroth G. Without their consent it may not be reproduced or given to third parties. he data specified above only serves to describe the product. No statements concerning a certain condition or suitability for a certain application can be derived from our information. he details stated do not release you from the responsibility for carrying out your own assessment and verification. It must be remembered that our products are subject to a natural process of wear and ageing.